Beware! Working in confined spaces carries significant risks

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Since the beginning of this year, there have been a high number of incidents of poisoning, asphyxiation in confined spaces, and dust explosions in the industrial and trade sector. As summer arrives, the hot weather causes temperatures in confined spaces to rise, making it easier for toxic and harmful gases to accumulate and evaporate. What should we do to prevent accidents in confined space operations? What is a confined space? A confined space refers to a space that is enclosed or partially enclosed, has narrow entrances and exits, is not designed as a permanent workplace, has poor natural ventilation, and is prone to the accumulation of toxic and harmful substances, flammable and explosive materials, or insufficient oxygen levels. Defined as a confined space, it generally needs to meet the following three conditions: it must have sufficient volume to allow a person to enter completely ； Imports and exports are narrow or restricted ； It is not designed as a space for long-term use. Confined spaces can be divided into three categories. ★Enclosed and semi-enclosed equipment. Including cabins, storage tanks, on-vehicle tankers, reaction towers, pipelines, boilers, tank trucks, etc. ★Underground structures. This includes underground pipelines, basements, underground structures, hidden ditches, tunnels, culverts, pits, abandoned shafts, cellars, sewage tanks (wells), biogas digesters, septic tanks, sewers, etc. ★Buildings on the ground. These include storage rooms, mash pits, fermentation tanks, waste stations, greenhouses, cold storage, grain silos, material bins, flue ducts, etc. What are the job-related hazards? ★ Poisoning hazards: Confined spaces are high-risk work areas where toxic and harmful gases such as hydrogen sulfide, methane, and carbon monoxide can easily be generated, leading to poisoning and suffocation of workers. Hazardous substances may already be present in confined spaces, or they may accumulate over time as work is carried out. Common examples include hydrogen sulfide. Hydrogen sulfide is easily generated when cleaning and unclogging sewers, septic tanks, wastewater tanks, and cellars. Carbon monoxide. In municipal construction and road construction, damage to gas pipelines can easily lead to the accumulation of carbon monoxide ； During equipment maintenance, carbon monoxide remaining inside the equipment may leak. Benzene, toluene, xylene. When applying anti-corrosion coatings in confined spaces, organic solvents such as benzene, toluene, and xylene contained in the paint evaporate, resulting in high concentrations of toxic substances. ★Hypoxia is caused by an excessively low oxygen concentration in the air, which can lead to hypoxia and suffocation in people. Carbon dioxide. Carbon dioxide is heavier than air, and it accumulates in places such as mines, cellars, and ship cabins where ventilation is poor for extended periods, which can lead to low oxygen levels. Inert gases. In industry, inert gases are commonly used to flush containers such as reaction vessels and storage tanks. An excessive amount of inert gas remaining in these containers can lead to simple oxygen deficiency or suffocation. ★Fire and explosion hazards: When the concentration of flammable and explosive substances in the air is too high, they can cause explosions or fires when exposed to fire. ★Other hazards in work activities may include falls, drowning, object strikes, electric shocks, and more. What are the characteristics of the accident? ★Seasonal patterns show that from March to October each year is a period when accidents in confined space operations are likely to occur, with the spring and summer seasons being particularly problematic. Hot and humid weather hinders ventilation in confined spaces, allowing toxic and harmful gases to accumulate more easily. Furthermore, due to the hot weather, some workers have a weak sense of safety and remove their protective masks without permission; such actions are extremely dangerous. ★Blind attempts to rescue lead to an increase in casualties. Statistics show that in most accidents occurring in confined spaces, improper handling and blind rescue efforts are the reasons behind the rise in casualties. The accident revealed significant issues in certain companies regarding risk prevention and control, management of work in confined spaces, and employee training. After poisoning and asphyxiation incidents occurred, some supervisors and rescuers risked entering confined spaces to carry out rescue efforts without taking any effective protective measures. ★There are misconceptions regarding the identification of confined spaces; some companies have wrong ideas about them, and workers do not have a clear understanding of what confined spaces are, failing to recognize the hazards present in such spaces. To this end, enterprises should conduct thorough inspections of confined spaces, clearly identify the risks associated with working in such spaces, and enhance relevant training and education. ★The lack of rescue equipment is one of the reasons for the high mortality rate in confined space operations. As for how to carry out such tasks, in accordance with the **Five Provisions on Safe Operations in Confined Spaces issued by the State Administration of Work Safety, enterprises must implement a strict approval system for such operations, and it is strictly prohibited to enter confined spaces for work without authorization ； It is necessary to follow the order of \"ventilation first, then testing, and finally work\"; working without proper ventilation or successful testing is strictly prohibited ； Personal protective equipment against poisoning and suffocation must be worn, safety warning signs must be installed, and it is strictly prohibited to carry out operations without such protective measures ； Safety training must be provided to workers, and it is strictly prohibited for them to start working without passing such training ； Emergency measures must be established, emergency equipment must be available on site, and reckless attempts at rescue are strictly prohibited. ★Evaluate the working environment before starting work, analyze hazardous factors, and implement a work approval system ； Clarify the on-site personnel and their safety responsibilities ； Inform about harmful factors and prevention measures, and carry out supervision ； First, ventilate the confined space and test the concentrations of flammable gases, explosive dusts, toxic and harmful gases, etc., to ensure they meet relevant standards before starting work. ★Implement ventilation measures during work to ensure good air circulation ； In the event of ventilation system failures, oxygen levels falling below the specified limits, or toxic and harmful gas concentrations exceeding the allowed levels, operations must be stopped immediately; all workers present should be accounted for and evacuated from the site ； Conduct periodic or continuous monitoring of harmful factors ； The supervisor must remain in contact with the workers and must not leave the site. ★When a task is interrupted and the interruption lasts for more than 30 minutes, ventilation must be carried out again before re-entering the confined space; entry is only permitted once the air quality has been verified as satisfactory. ★After the work is completed, the person in charge of the work site and the supervisors should clean up the site and evacuate the workers. How to prevent problems before they occur? ★To strengthen work safety management, enterprises should establish and improve a responsibility system for safe production in confined space operations, clearly defining the duties of the responsible persons, workers, and supervisors ； Formulate specific operation plans, procedural guidelines, emergency rescue plans, and safety technical measures, and strictly implement all safety requirements to ensure effective emergency rescue efforts. ★When conducting safety training, employees should be informed about the hazardous factors present in confined spaces and the preventive measures that need to be taken, in order to enhance their awareness of self-protection ； Organize employees to learn the safety operating procedures, and teach them how to use testing instruments and protective equipment. In the event of an accident, those present at the scene should immediately call the police; attempts at rescue without proper planning are prohibited, and rescuers must take appropriate protective measures. ★Pay attention to temporary operations: Before carrying out temporary work in confined spaces, companies should thoroughly assess whether they have the capability to conduct such work, whether they have qualified personnel, whether the relevant rules and regulations are in place, and whether the emergency rescue equipment meets the required standards. Those that do not meet the requirements shall not organize construction work on their own. ★Companies equipped with the necessary equipment should have isolated respiratory protection devices, emergency communication equipment, on-site rapid testing equipment, high-power forced ventilation systems, emergency lighting equipment, as well as safety ropes, life lines, and safety ladders.